Part 7 - UNC Herbarium

POACEAE 921
12 Plant creeping extensively by slender rhizomes; leaf blades cauline, distichous, to 12 cm long.............S. virginicus
12 Plant loosely tufted, from short rhizomes; leaf blades basal or cauline, not distichous, 10-100 cm long.
13 Spikelets 1.5-2.2 mm long; first glume 0.5-0.8 mm long; leaves primarily basal ............................... S. indicus
13 Spikelets 4-8 mm long; first glume 2-5 mm long; leaves cauline and basal.
14 Lemma pubescent, usually conspicuously shorter than the palea; pericarp loose when moist ....................
............................................................................................................................................S. clandestinus
14 Lemma glabrous, about as long as the palea; pericarp gelatinous when moist.
15 Culms (1.4-) 2.0-5.0 mm thick; terminal sheath (1.3-) 1.5-6.0 mm wide; panicles with 12-35
primary branches, crowded, dense.......................................................S. compositus var. compositus
15 Culms 1.0-2.0 (-2.5) mm thick; terminal sheath 0.8-2.0 (-2.5) mm wide; panicles with 8-18 primary
branches, lax, loosely flowered ......................................................[S. compositus var. drummondii]
Sporobolus clandestinus (Biehler) A.S. Hitchcock, Rough Dropseed. Pd, Cp (GA, NC, SC, VA), Mt (VA): glades,
barrens, and thin soil of woodlands, also in dry sands; uncommon. September-October. This species is widespread in e. United
States. Wipff & Jones (1995) recommend reducing this taxon to a variety under S. compositus, because of its morphologic
similarity. While S. clandestinus and S. compositus are undoubtedly closely related, I prefer to retain the two as species. [=
RAB, C, FNA, F, G, HC, K, S, W, Z; = S. compositus (Poiret) Merrill var. clandestinus (Biehler) J. Wipff & S.D. Jones]
Sporobolus compositus (Poiret) Merrill var. compositus, Tall Dropseed. Pd (NC?, VA), Mt, Cp (VA): diabase glades and
barrens, limestone glades and barrens, disturbed areas over diabase or calcareous rocks; rare (NC Watch List, VA Rare).
September-November. This species and variety are reported for NC in a recent revision of the S. asper group (Riggins 1977);
little is known about the occurrence of this species in NC. The general range is centered in the Plains, but extending east into ne.
United States. The name S. compositus has nomenclatural priority over the more familiar S. asper (Kartesz & Gandhi 1995). [=
FNA, K; = S. asper (Michaux) Kunth var. asper – C, G, HC, Z; = S. asper – F, S]
* Sporobolus cryptandrus (Torrey) A. Gray, Sand Dropseed. Cp? (NC?): disturbed areas; rare, probably adventive from c.
and w. North America. This species is reported for NC by HC, F, and S. [= C, FNA, G, K, HC, S, X; > S. cryptandrus var.
cryptandrus – F]
Sporobolus curtissii (Vasey ex Beal) Small ex Scribner, Curtiss's Dropseed. Cp (GA, SC): moist, gummy-clay flatwoods;
uncommon (rare north of GA). September-November. E. SC south to c. FL. First positively documented for our area in 1993.
Earlier attributions of S. curtissii to NC and SC were apparently based on misapplication or confusion with S. teretifolius and/or
Sporobolus pinetorum. S. curtissii differs from other "bunchgrass" Sporobolus of our area in having the spikelets shortpedicelled
and appressed against the panicle branches (as opposed to long-pedicelled and spreading in S. teretifolius and
Sporobolus pinetorum). [= FNA, HC, K, S, Y]
*? Sporobolus domingensis (Trinius) Kunth, Coral Dropseed. Cp (GA): coastal sands?; rare, uncertain whether native or
introduced. Se. GA south to s. FL; West Indies, Mexico. The e. GA record (Glynn County) is at Univ. of Georgia (Sorrie, pers.
comm.). [= FNA, HC, K, S]
Sporobolus floridanus Chapman, Florida Dropseed. Cp (GA, SC): wet savannas; uncommon (rare north of GA). June-
September. Se. SC south to ne. FL, west to Panhandle FL. First positively documented for our area in 1995. Earlier attributions
of S. floridanus to NC and SC were apparently based on misapplication or confusion with Sporobolus pinetorum. [= FNA, K, Y;
< S. floridanus – GW, HC, S (also see S. pinetorum); the inclusion of S. floridanus in RAB was based on a misidentification of S.
pinetorum]
Sporobolus heterolepis (A. Gray) A. Gray, Prairie Dropseed. Mt (GA, NC, VA): barrens and glades over mafic,
ultramafic, and calcareous rocks (olivine, serpentine, limestone); rare (NC Endangered, VA Rare). August-September. The
primary distribution of S. heterolepis is in the Plains, with outliers east to nw. GA (Jones & Coile 1988), c. TN (Estes & Beck
2005), w. NC, w. VA, se. PA, ne. United States, and adjacent Canada in calcareous, mafic, or ultramafic glades, barrens, and
prairies. [= RAB, C, F, FNA, G, HC, K, W, Y]
* Sporobolus indicus (Linnaeus) R. Brown, Smut Grass, Blackseed. Cp, Pd, Mt (GA, NC, SC, VA): roadsides, lawns,
disturbed situations; common, introduced from the tropics of Asia. July-October. [= C, FNA, GW, W; > S. poiretii (Roemer &
J.A. Schultes) A.S. Hitchcock – RAB, F, G, HC; > S. indicus – HC; = S. berteroanus (Trinius) A.S. Hitchcock & Chase – S; = S.
indicus var. indicus – K]
Sporobolus junceus (Palisot de Beauvois) Kunth, Sandhills Dropseed. Cp (GA, NC, SC), Pd (GA, NC, SC, VA): sandhills,
other dry, open areas; common, uncommon in Piedmont (VA Rare). September-October. Se. VA south to FL and west to se.
TX. [= RAB, C, F, FNA, G, HC, K, Y; = S. gracilis (Trinius) Merrill – S]
Sporobolus neglectus Nash, Barrens Dropseed. Mt (VA): dry rocky barrens and outcrops, over calcareous rocks (such as
limestone or dolomite); rare (VA Rare). August-September. ME west to ND, south to NJ, w. VA, TN, LA, and TX; apparently
disjunct in WA and AZ. S. ozarkanus, S. neglectus, and S. vaginiflorus form a still very poorly understood complex. [= C, F,
FNA, G, HC, K, S, W]
Sporobolus ozarkanus Fernald, Ozark Dropseed. Pd (NC): diabase glades; rare (NC Rare). September-October. KY west
to KS, south to e. TN, AR, and TX; disjunct in c. NC. In Granville County, NC, it is associated (on glades of diabase, a mafic
rock) with other taxa with affinities to midwestern glades and prairies: Oligoneuron rigidum, Oligoneuron album, Baptisia
australis var. aberrans, Symphyotrichum depauperatum, Silphium terebinthinaceum, Parthenium auriculatum, Ruellia humilis,
and others. S. ozarkanus, S. neglectus, and S. vaginiflorus form a still very poorly understood complex. [= C, F, G, HC, K; = S.
vaginiflorus (Torrey ex A. Gray) Wood var. ozarkanus (Fernald) Shinners – FNA, K]
Sporobolus pinetorum Weakley & P.M. Peterson, Carolina Dropseed, Savanna Dropseed. Cp (GA, NC, SC): wet
savannas, savanna-pocosin ecotones, sandhill-pocosin ecotones, and extending upslope into mesic flatwoods or loamy or clayey